title: Purification and characterization of a novel immunomodulatory protein from the medicinal mushroom Trametes versicolor.
abstract: Bioactive proteins represent an important group of functional agents in medicinal mushrooms. Trametes versicolor (L.) Lloyd is a mushroom frequently used in traditional Chinese medicine for its anti-tumor and immunomodulatory activities. A new immunomodulatory protein from T. versicolor, named TVC, was purified by ammonium sulfate precipitation, ion-exchange chromatography and gel filtration chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the purified protein revealed a single band with a molecular weight of 15.0 kD. Native polyacrylamide gel analysis revealed a band at 30 kD, indicating that TVC exists in solution as a homodimer. Isoelectric focusing showed that TVC was an acidic protein with an isoelectric point of 4.0. TVC was found to lack carbohydrate modifications (based on periodic acid/Schiff staining) and it does not agglutinate mouse red blood cells, suggesting that TVC is not a lectin-like protein. Biological activity assays demonstrated that TVC can enhance the proliferation of splenocytes, while it has no stimulatory effects on CD4(+) and CD8(+) T cells. TVC markedly increases the proliferation of human peripheral blood lymphocytes in a dose-dependent manner and enhances the production of both nitric oxide and tumor necrosis factor-alpha by lipopolysaccharide-induced murine macrophages. The results indicate that TVC is an immunostimulant that can boost immune response. Comparison of the N-terminal amino acid residues and mass spectrometry results with the protein database revealed no homologous proteins.
authors.affiliation: Key Laboratory of Systematic Mycology and Lichenology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Huaan
authors.initials: H
authors.lastname: Wen
authors.forename: Yongjie
authors.initials: Y
authors.lastname: Zhang
authors.forename: Min
authors.initials: M
authors.lastname: Aa
authors.forename: Xingzhong
authors.initials: X
authors.lastname: Liu
mesh_terms: D000818:Animals; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000494:pharmacology; D006386:Hemagglutination Tests; D006801:Humans; D007155:Immunologic Factors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D008516:Medicine, Chinese Traditional; D051379:Mice; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D009569:Nitric Oxide / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D055454:Trametes / Q000737:chemistry*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D007155:Immunologic Factors; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide